报告题目 (Title):CGMB(Cosmic Gravitational
Microwave Backgrounds) and the dEGB (dilaton-Einstein-Gauss-Bonnet)
Cosmology(宇宙引力微波背景与爱因斯坦-高斯-博内宇宙学)
报告人 (Speaker): Bum-Hoon Lee(韩国西江大学)
报告时间 (Time):2026年4月9日(周四)10:00
报告地点 (Place):校本部 G楼313会议室
邀请人(Inviter):葛先辉,尹璐
报告摘要:We
begin by presenting the motivation for frameworks beyond Einstein's
gravity and the ΛCDM paradigm, both from the theoretical and
observational aspects . Sources and detectors of Gravitational Waves
(GWs) are briefly reviewed with GWs as a tool for testing or
constraining theories especially beyond Einstein's General Relativity
theory. The main focus is on the CGMB from the hot plasmas in the early
universe whose pea frequency is close to 100GHz. Next, our discussion
will be on the cosmology of dilaton-Einstein-Gauss-Bonnet (DEGB)
gravity. This represents one of the simplest extensions through the
inclusion of higher-curvature terms. Particular attention is given to
the emergence of a novel phase within dEGB cosmology at high
temperatures, supplementing the established radiation, matter, and dark
energy-dominated phases characteristic of the ΛCDM model. Out of the
many implication of dEGB cosmology, we describe the impact to the CGMB
from the hot plasmas consisting of the standard model particles in the
early universe. The sources and propagation of the GWs depend on the
gravity theory. We point out that CGMB can be enhanced up to the visible
range for the detectors near future with the present technology. This
should lead either to the new discovery of the Ultra High Frequency
gravitational waves of CGMB or the constraints to the DEGB theory if
not.